Deano
Veteran Member
Here is a battery charge chart. If it reads 12 volts, it is not even at 50%
Battery or starter problem? How do I know/test which it is? Kubota L3940
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Here is a battery charge chart. If it reads 12 volts, it is not even at 50%
Deano
Veteran Member
View attachment 433205
Here is a battery charge chart. If it reads 12 volts, it is not even at 50%
Here is a battery charge chart. If it reads 12 volts, it is not even at 50%
SPYDERLK
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You really need a voltmeter and good probes and clip leads. Otherwise youre in flail mode. You can get a cheap digital one for under $10 @ Harbor Freight. With it you can tell what V you have in key conditions. That will quickly lead you to the problem area.
larry
rScotty
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Sounds like a bad battery to me. The ratatatat was most probably the last gasp of the battery which just had enough juice left to activate the starter solenoid....but not enough to turn the starter.
Yes, you can jump it from any 12 volt car or truck just like you would jump any other car or truck. Absolutely no problem with doing that and no difference from jumping anything else. It makes a good test, because if the battery went flat for some other reason than just being too old...like if you left the key on.....then letting it run for half an hour at a medium fast idle ought to charge it back up and you are good to go. Alternately, if the battery really is on it's last legs then chances are good that after you run the tractor for that half an hour the battery will hold enough charge for ten minutes or so to start a warm engine. If it does that you will know for sure that the starter is OK and it is new battery time.
Yes, the dash lights should light up normally when it is jumped. Once it is jumped and it starts, disconnect the jumpers just like you always do and it should continue to run normally with all the dash lights and intstruments working normally. If that is the case then you know that the alternator is good......and since the starter worked fine when when you jumped it you are back to it being new battery time just like above.
As easy as those tests are, if the battery is 5 years old or older there's no real downside to just skipping all the tests and simply replacing the battery. I say that because number one I always suspect the battery first, and second....if you are dealing with a battery - particularly an OEM battery - that old then it's a pretty good bet that you will need a new one within two or three years anyway. So it's a pretty good decision to just go get a good battery and expect it will last you twice as long. For batteries, I like the AGM types. My personal favorite is the Optima Red Top.
luck, rScotty
grsthegreat
Super Star Member
One of the best.... And yet not very expensive... Tools ive purchased is a carbon pyle battery tester.
It does a 15 second actual load test on a battery. For instannce, for a group 26 battery rated at 550 CCA, I PLACE A 250 amp load on it for 15 seconds. The easy to read analog meter shows condition of battery. It doesnt just read voltage on a unloaded battery..it actually loads the battery.
Ive had batteries that read 12.5 volts but totally fail under load
It does a 15 second actual load test on a battery. For instannce, for a group 26 battery rated at 550 CCA, I PLACE A 250 amp load on it for 15 seconds. The easy to read analog meter shows condition of battery. It doesnt just read voltage on a unloaded battery..it actually loads the battery.
Ive had batteries that read 12.5 volts but totally fail under load
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I agree 100%... I bought mine about 30 years ago and it was money well spent.
My friend had replaced several batteries in his Mustang... and it sure sounded like a battery problem.
My tester has a nice large meter and his battery passed load test with flying colors... then I told him to start the car and the draw pegged the meter.
It was a bad starter... a bronze bushing had fallen out so the armature was out of alignment... he was on his third battery... only time it was the starter for me.
My friend had replaced several batteries in his Mustang... and it sure sounded like a battery problem.
My tester has a nice large meter and his battery passed load test with flying colors... then I told him to start the car and the draw pegged the meter.
It was a bad starter... a bronze bushing had fallen out so the armature was out of alignment... he was on his third battery... only time it was the starter for me.
Coyote machine
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Chances are the battery is in need of replacement. Because of it's age and 500 hours on your tractor it doesn't get a huge amount of consistent use. Batteries die for a long list of reasons.
Doing a load test is a good way to determine if a battery is good, bad, etc., BUT the load test is only accurate when the battery has been fully charged beforehand. Load testing a near dead battery can kill it dead, but more importantly is a near dead battery will almost always fail a load test and that result is not helpful in determining if the battery is at the end of it's useful service life.
Starters can and do go bad at times, but before hitting anything with a hammer, find out what the actual problem is. Jumping to conclusions without facts to verify the cause is a huge waste of time and often money, and unnecessary part replacement.
Get and use a VOM meter, as suggested already, or disconnect and take the battery to a reputable place, have then charge the battery, and then do a load test. Either way you need to rule out the battery as the problem, or confirm that it is the problem and replace it with the correct size and capacity new battery.
Report back results or questions....
Doing a load test is a good way to determine if a battery is good, bad, etc., BUT the load test is only accurate when the battery has been fully charged beforehand. Load testing a near dead battery can kill it dead, but more importantly is a near dead battery will almost always fail a load test and that result is not helpful in determining if the battery is at the end of it's useful service life.
Starters can and do go bad at times, but before hitting anything with a hammer, find out what the actual problem is. Jumping to conclusions without facts to verify the cause is a huge waste of time and often money, and unnecessary part replacement.
Get and use a VOM meter, as suggested already, or disconnect and take the battery to a reputable place, have then charge the battery, and then do a load test. Either way you need to rule out the battery as the problem, or confirm that it is the problem and replace it with the correct size and capacity new battery.
Report back results or questions....
skyhook
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Same here.
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The simple and quick way would be to use a good battery to jump it...
If it cranks well... you know the battery either needs a charge or replacement.
Had good luck with some of the automatic battery chargers that pulse... left them on for a weekend and if it starts... you are good for now... if not, time to replace the battery.
If it cranks well... you know the battery either needs a charge or replacement.
Had good luck with some of the automatic battery chargers that pulse... left them on for a weekend and if it starts... you are good for now... if not, time to replace the battery.
k0ua
Epic Contributor
Same here.
That would be what is known as a high internal resistance. Here is a thought experiment. Take voltmeter and measure the poles of the battery. OK let's say it is 12.6 volts. Now put a 1000 ohm resistor in series with one of the battery terminals. Measure the voltage. It should still be 12.6 Volts correct? Now try to start you tractor thru your resistor, will the tractor crank? What will the voltage be on the tractor end of the resistor? What will the voltage measure on the battery end of the resistor? E=IR. P=EI. E is electromotive force also known as volts. I is current measured in amperes. R is resistance measured in Ohm's.
The point is that your battery has an high internal resistance and the voltage will drop significantly when the load is placed across it. Batteries with low internal resistance will deliver significant amounts of current at near open circuit voltages with minimal voltage drops when a low resistance load is placed across their terminals. High currents at a given voltage equals power able to do work like spin a starting motor.
